General-purpose registers are represented by predefined symbols of the
form GRnnn (for global registers) or LRnnn
(for local registers), where nnn represents a number between
0 and 127, written with no leading zeros. The leading
letters may be in either upper or lower case; for example, gr13
and LR7 are both valid register names.
You may also refer to general-purpose registers by specifying the
register number as the result of an expression (prefixed with %%
to flag the expression as a register number):
%%expression
--where expression must be an absolute expression evaluating to a
number between 0 and 255. The range [0, 127] refers to
global registers, and the range [128, 255] to local registers.
In addition, as understands the following protected
special-purpose register names for the AMD 29K family:
vab chd pc0
ops chc pc1
cps rbp pc2
cfg tmc mmu
cha tmr lru
These unprotected special-purpose register names are also recognized:
ipc alu fpe
ipa bp inte
ipb fc fps
q cr exop